Moldavite is a tektite from a meteor crash that occurred 15 million years ago in the Bohemian Plateau of the Czech Republic. Moldavite gets its name in part from being found near the Moldau River. Similar to obsidian or volcanic glass, in his structure we can see bubble and curved striae. The hardness is 5.5 and the silica content is very high: about 80%. Other minerals are: Iron,Magnesium,Calcium,Aluminum,Potassium and Sodium.